# -*- coding: utf-8 -*-
#


def _s4(a, z):
    return [
        [+a, +a, z],
        [-a, +a, z],
        [+a, -a, z],
        [-a, -a, z],
        ]


def _s4_0(a, z):
    return [
        [+a, 0.0, z],
        [-a, 0.0, z],
        [0.0, +a, z],
        [0.0, -a, z],
        ]
